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    <title>Document</title>
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<script>
    var str = 'momo_list';

    function Conversion(str) {
        var arg = str.split('');
        var index = arg.indexOf('_');
        arg.splice(index, 1);
        arg[index] = arg[index].toLocaleUpperCase();
        return arg.join('');
    }

    console.log(Conversion(str));
    console.log(Conversion('asjdoai_idajwodi'));
    

</script>

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